Minn. R. agency 151, ch. 1346, MINNESOTA MECHANICAL CODE, pt. 1346.1204

Current through Register Vol. 49, No. 12, September 16, 2024

Part 1346.1204 - SECTION 1204 PIPE INSULATION

IMC Section 1204.2 is amended to read as follows:

1204.2 Required thickness. Hydronic, steam, and condensate piping shall be insulated in accordance with this section.

Exceptions: Piping insulation is not required for:

1. Piping installed within HVAC equipment; or

2. Piping installed in basements, crawl spaces, and cellars.

Insulation Thickness for Nominal Pipe Diameters

Fluid Temperature Range oF	Runouts (see item C)	1 inch (25.4 mm) and Less	1.25 to 2" (31.7 to 50.8 mm)	2.5 to 4" (63.5 to 101.6 mm)	5 to 6" (127 to 152 mm)	8" (203 mm) and Larger
Piping System Type - Heating
Above 350	1.5	2.5	2.5	3.0	3.5	3.5
251-350	1.5	2.0	2.5	2.5	3.5	3.5
201-250	1.0	1.5	1.5	2.0	2.0	3.5
141-200	0.5	1.5	1.5	1.5	1.5	1.5
105-140	0.5	1.0	1.0	1.0	1.5	1.5
Piping System Type - Cooling
40-55	0.5	0.5	0.75	1	1	1
Below 40 (see item D)	1	1	1.5	1.5	1.5	1.5

A. Insulation thickness in this section assumes a k-value of 0.27. If the k-value of a product is less than 0.22, then the thickness must be adjusted to have an equivalent R-value.

B. For piping exposed to outdoor air, insulation thickness must be 0.5 inch (12.7 mm) greater than required in the table.

C. This column applies only to runouts (branches) 2 inches (50.8 mm) in diameter and less, not exceeding 12 feet (3658 mm) in length, to individual terminal units. All other runouts shall meet the requirements given in other columns in the table, as appropriate.

D. For applications with fluid temperatures of 32 ^oF (0 ^oC) and below, a vapor retarder shall be installed in accordance with IMC Section 604.11.

Minn. R. agency 151, ch. 1346, MINNESOTA MECHANICAL CODE, pt. 1346.1204

29 SR 299; L 2007 c 140 art 4 s 61; art 13 s 4

Statutory Authority: MS s 16B.59; 16B.61; 16B.64; 326B.101; 326B.106; 326B.13